3. On the one hand, the whole scientific world followed the progress of the first successful clone, Dolly the sheep. _________________________________________________ 4. However, the problem that she later developed a serious lung disease bothered scientists. _________________________________________________ 5. The fact that Dolly died when she was quite young disappointed people the world over. _________________________________________________ 答案:3. Dolly the sheep 4. that she later developed a serious lung disease 5. that Dolly died when she was quite young